Method for controlling the contours of rayon cakes



W. BAKKER May 23, 1950 METHOD FOR CONTROLLING THE CONTOURS 0F RAYON CAKES Filed NOV. 28, 1947 diatom Patented May 23, 1950 METHOD FOR CONTROLLING THE CON- TOURS OF RAYON CAKES Willem Bakker, Arnhem, Netherlands, assignor to American Enka Corporation, Enka, N. 0., a corporation of Delaware Application November 28, 1947, Serial No. 788,701

In the Netherlands June 16, 1947 l This invention relates to the pot spinning of rayon yarn and is more particularly related to the control of the contours of the wound cake between the termination of the spinning period and the commencement of the first aftertreating operait is particularly pronounced where thethread tion. has been in contact with water or aqueous solu-v When viscose rayon is spun according to the pot tions after it has left the spinning bath and bespinning process, the completed cake is orfore it enters the spinning pot. This situation ocdinarily removed from the pot by turning the curs in two-bath spinning where the thread is pot upside down and discharging the cake onto stretched in a second dilute aqueous bath be,- a flat plate. The axial section of such a cake tween the spinning and the collection. Furconforms to the axial section of the frustum of thermore, it is found that in cases of high denier a hollow cone, the top and bottom as well as the yarns such as are used in the production of tire inner and outer surfaces being straight. The yarns, the growth phenomenon is serious. cake, in this condition, is ordinarily stored for a It is therefore an object of this invention to period of time in order to permit the regeneraovercome the foregoing difiiculties and to provide tion of the cellulose to proceed to conclusion, and for the storage of freshly spun cakes in such a then the cake is placed between two plates which way as to prevent distortion of the cake contour are parallel to each other and normal to the long with its concomitant disadvantages. axis of the cake in order to subject it to after- It is contempla d according to the present intreatment such as t removal of acid by washvention to locate the freshly spun cake between m or color improvement by bleaching two spaced plates located a distance apart equal Because of the construction of conventional apto the height of the freshly h cake and the paratus for the efiecting of the aftertreatment, distance between e Plates whlch hold the cake it is absolutely essential that the spacing between duneg the aftertreeitmg f the plates which hold the cake during aitep It IS a further ob ect of this invention to contreatment be maintained at a fixed value. It has trel e eenteuref the fleshly Spun eakedmng been found, however, that during the storage e e i g era 1ons n suc manner a e p an opera ors 532: igg g izfig gg gg g mf 1 323 53 3 2 are protected from the evolution of dangerous the upper edge of the inner surface so that the gzj g as carbon disulphlde durmg the aging upper surfaceof the cake, after storage, is no longer a fiat annulus but rather, slopes upwardly g g Objects and advalitages of thisdnvenflon toward the center. When a cake deformed in W e apparent confident-e0? of e follow mg detailed description thereof in con unction this manner is placed between the two plates with the annexed drawings wherein, for aftertreatment it is apparent that the raised Figure 1 is a vertical sectional view of a freshly port-ion must be again depressed if e plates i spun cake of rayon yarn placed in storage for to assume the desired spaced relation relative aging m accordance with the principles of the to one another which is required by the machine. 40 present invention;

As a matter of fact, it has been found that pres- Figure 215 a top plan View of the Subject matter sures reaching several tens of kilograms per cake of Figure and must be' applied in order that the plates at the top Figure 3 i a perspective view of the details and bottom of the cake can be moved together of a latching mechanism constituting apart of to their normal operating position. The exertion the present invention.

of pressures of this order has a tendency to com- Referring now to the drawings in greater detail, press the alsed peetienef the cake and 3 form the arrangement shown consists of a bottom plate an annulus Pmjectmg Into the hollow Interior assembly In including a collar H which has ex- Of the cake near the top edge thereof- During tending from the base thereof an annular flange the compression of the cake and the formation I2. Near the center of the bottom plate assembly of i n r ad layers r required to Slide l0 there is provided a frusto conical boss I3 which over one anot Which y cause damage, d extends considerably above the upper edge of the the resultin h p Of the Cake, that the prescollar II. It can be seen, however, that a flat anence of the inwardly protruding annulus near nular space is provided between the boss I3 and the top of the cake, causes the cake to wash un- 66 the collar H, and it is this space on which the 1 Claim. (01. 18-54) evenly and results in bad unwinding and excessive waste.

While the foregoing phenomenon is present to some extent in all cakes, it has been found that cross section of such shape that the top edge of'a'." standard spinning pot will fit into it; Thusuthe" inverted bottom assembly fits in centralized posi tion around the edge of a spinning pot. q M It should also be noted that the b'ottonif'plate assembly has been so constructed that ber of these can be piled one upon another so that they occupy as little space-as"possible:

The remainder of the apparatus discldsed in Figures 1 and 2 can probably be best understood by reference to the use thereof in actual peaches.

At the dofi, the bottom plate assembly is placed upside down on the spinning p'dt'as 'so'o'ii as the spinning pot lid has been removed. The bottom plate assembly fitsin a centralized position on thespinnin'gpot. The pot-"and platej assembly are" then inverte'cl' so that the cake M rests' in the position shown in Figure 1. Th'e'pot is tlienrein'oved and-the lid l5 isplaced in the'p'o sition" shown in Figure l overlying the" cake I4, The" height of the lid has been so chosenthat, in' 'its' coactin'g position with the bottom plate assembly, the vertical distancebetween the u per surface of the'ann'ul'ar space betweenthe boss and" the'- collar the bottom plate assembly and" thecorresponding s'uriace'of the'lid I5"isequal to theheight'ofthe cake, with perhaps one or two mms. to-s'piare to compensate? for minorvariations inthe'height'of'thespiin cake; 7 g

The lid i5 is attached to the bottom assembly by means of two flat steel plat'es-fi and I8 which can best be seen in'- Figure-3w The two steel plates arep'ivotall'y mounted at I9 and 2 0 respectively and are spring-urged such-that the steel plate l1 is'biase'd' in a counterclockwise di r'eetion; as viewed in Figure 2, while the steelplate" I8 is biased inaclockwise'direction;as it is iii that -figu r;- The steel pares cooperate-with a bolt 2'! which-is held by "a nut 22" a't the" we of the boss i3' iri the bottom assembly 105- The belt 2 I is cylindrical throughout rh'o'st'of its-length" but is provided with an annular groove at 22 adapted-for the'recep'tioiioi edge portions of the steel plates 1'! and 18. When the lid I5 is macaw in 'operative positioitthest'eel plates" i1 and i8 are'moved apart during-passage o'ver thle -rounded ofitopport-ion of the bolt 2i; and,wheii they register with theplaneof the' groove at-ZZQ-th'ey' fall 'into it'and so l'ockithe bolt to-the'lid assembly.

order to release the plates I*1- and i8; 2; key-' hole at 23 is provided in" which a key, not'sh'owm may be mounted for rotation: to bear against" vertical flangesi'ia and- Ilb of the niembers'""l1 and I8 to move them apart andiout o'ftheslot 22";to permit removal of thelid l 5.-

Duri-ng theaging period between the insertlon= of the cake into the apparatus shown in-Figures -1- and 2 and'the removalthere'of from that-apparatios-preparatory to socking for thefirst-of-the aitertreatin-g operations; it is apparent thatthew height of thecake cannot grow more-thana-very fewunms. After the aging period there is no tendency for the height of the cake to change:

e any more so that all cakes which are stored in the apparatus of the present invention have flat top and bottom surfaces lying equal distances apart, and these are readily received in between the plates which hold them for the aftertreating operation. It rnig'ht be-si ppos'ed that; since cakes during the" agi'ng' period have a -te'nden'eyto grow upwardly, that they would exert a very large I force on the bottom plate and lid constituting -=the assembly-of Figures 1 and 2.

m It has been found -however that although a freely grown cake requires very considerable force to flatten it, the restrain n forc'e'iieoessary to maintain th cake inth desiredsliape is relatively slight.

Itisappareiitrrdia the foregoing, as far as cake 7 growth is coneernde the results could be achieved any arrangement involving two spaced plates bearing on the bottom and top surfaces of the cakeanu held in a fixed relative position. An additional advantage of the present construction is; however:thatthe'gases' which evolve during the agirig o'f' th'ec'iakel such as'carbon disulpli iizle, arejretained within the housing defined by he b'ottdiii plate assembly llland the lid FE' sitIiat' storing the cakes during the aging period, is fi e'e 'of the" dan'gemus'and tbxic gases evolved. W-lierPth''cake a'r emoved for washing this can be deiie in an rea o'f good veritilation and' evii theboxes selves can be provided' -with vents sothat they'cafi be evaci'i-atedbefore-tliw ar epeaed r I 7 It is perfectly e15 "areathat transportation I tli'e'se boxed cakes- 1s much-- more easily efiectecfthan tfansportation of 'thecakesiri unboxed for-iii since dafigf-of ifijiii y to theyarh ca'l's'e is g'i ea'tly' reduc d;

while the foregoing 'i-hve'ntioh has been-de scribed-with referenceto "but a single embodiment thereof; it is tobe understood that variousmodi fications-are contemplated" as lying within the" scope of the-appended claim.

What is claimed isz VThe'method of inhibiting the axial growth-of freshly spun; cakes of rayon yarnthat comprises removing the cover fromthe spinning potat the termination of thespinning period, substitut ing a plate presenting a; flat cake; end-support" ing surface, ir'ivertingthe 'pot withv the plateinposition: removing the pot while leaving-the cake? on the plateiloca'ting another member having a fiat yarn end-co'ritactifigsui face overv the upper end of the" c'a'ke, drawiiig'said 'meinber toward said plate until -thkei member almost touches" theupper 7 e'riod afteithe" formation of'the cakeand'prier 

